Communication terminal, communication function starting method, and computer-readable recording medium

ABSTRACT

A communication terminal includes a display control unit configured to display, on a display unit, a function selecting screen that contains a first icon for receiving a selection of a first communication function and a second icon for receiving a selection of a second communication function. The first communication function is to provide communication using a signaling protocol for connecting to or disconnecting from a destination of communication and an encoding protocol for encapsulating communication data in IP packets. The second communication function is to provide communication using the same signaling protocol and a different encoding protocol. The communication terminal also includes a receiving unit configured to receive a selection of the first icon or the second icon; and a starting unit configured to start the first communication function and the second communication function in response to the selection of the first icon and the second icon, respectively.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation application of U.S. patentapplication Ser. No. 14/395,270, filed Oct. 17, 2014, which is aNational Stage application of PCT/JP2013/063224 filed on May 1, 2013,and claims priority to Japanese Patent Application Nos. JP2013-081931,filed on Apr. 10, 2013, and JP2012-104418, filed on May 1, 2012. Theentire contents of the above-identified applications are incorporatedherein by reference.

TECHNICAL FIELD

The present invention relates to an invention for starting any of aplurality of communication functions using different communicationsystems.

BACKGROUND ART

Recently having come into general use is a communication system forenabling a teleconference over a communication network such as theInternet, because of a demand for cutting a traveling cost and travelingtime. When such a communication system is used, a teleconference can beheld by allowing image data and audio data to be exchanged among aplurality of communication terminals (see Japanese Patent ApplicationLaid-open No. 2008-227577).

In addition, disclosed is a video phone system providing onecommunication terminal with two different communication functions usingdifferent communication protocols, e.g., the personal digital cellular(PDC) protocol and the personal handy phone system (PHS), respectively,and communication is established while switching these two differentcommunication protocols (see Japanese Patent Application Laid-open No.2001-326972).

In these conventional two communication protocols, a signaling protocolfor connecting to and disconnecting from a destination and an encodingprotocol for encoding call data are both different. In other words, sucha conventional communication terminal is a single housing merelyprovided with two different communication functions using completelydifferent communication protocols, and causing one of the functions tooperate exclusively. Therefore, it has been impossible for a pluralityof communication functions using the same signaling protocol butdifferent encoding protocols to be used on the same terminal.

DISCLOSURE OF INVENTION

It is an object of the present invention to at least partially solve theproblems in the conventional technology.

According to an embodiment, there is provided a communication terminalthat includes a display control unit configured to display, on a displayunit, a function selecting screen that contains a first icon forreceiving a selection of a first communication function and a secondicon for receiving a selection of a second communication function, thefirst communication function being to provide communication using asignaling protocol for connecting to or disconnecting from a destinationof communication and an encoding protocol for encapsulatingcommunication data in internet protocol (IP) packets, the secondcommunication function being to provide communication using thesignaling protocol of the first communication function and an encodingprotocol different from that of the first communication function; areceiving unit configured to receive a selection of the first icon orthe second icon; and a starting unit configured to start the firstcommunication function in response to the selection of the first icon,and start the second communication function in response to the selectionof the second icon.

According to another embodiment, there is provided a communicationfunction starting method that includes displaying, on a display unit, afunction selecting screen that contains a first icon for receiving aselection of a first communication function and a second icon forreceiving a selection of a second communication function, the firstcommunication function being to provide communication using a signalingprotocol for connecting to or disconnecting from a destination ofcommunication and an encoding protocol for encapsulating communicationdata in internet protocol (IP) packets, the second communicationfunction being to provide communication using the signaling protocol ofthe first communication function and an encoding protocol different fromthat of the first communication function; receiving a selection of thefirst icon or the second icon; starting the first communication functionin response to the selection of the first icon; and starting the secondcommunication function in response to the selection of the second icon.

According to still another embodiment, there is provided acomputer-readable recording medium with an executable program storedthereon. The program instructs a computer to execute the communicationfunction starting method according to the above embodiment.

The above and other objects, features, advantages and technical andindustrial significance of this invention will be better understood byreading the following detailed description of presently preferredembodiments of the invention, when considered in connection with theaccompanying drawings.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a general schematic of a communication system according to anembodiment according to the present invention;

FIG. 2 is a conceptual schematic illustrating communications exchangedwhen communication is established between communication terminals havinga dedicated terminal function;

FIG. 3 is a conceptual schematic illustrating image qualities of imagedata exchanged according to the H.264 Scalable Video Coding (SVC)standard illustrated in FIG. 2;

FIG. 4 is a conceptual schematic illustrating communications exchangedwhen communication is established between terminals having anon-dedicated terminal function;

FIG. 5 is a conceptual schematic illustrating image quality of imagedata exchanged according to the H.264 Advanced Video Coding (AVC)standard illustrated in FIG. 4;

FIG. 6 is an external view of the communication terminal according tothe embodiment;

FIG. 7 is a schematic of a hardware configuration of the terminalaccording to the embodiment;

FIG. 8 is a schematic of a hardware configuration of a communicationmanagement system, a relay device, a program providing system, or amaintenance system according to the embodiment;

FIG. 9 is a functional block diagram of a communication terminal, arelay device, and a communication management system included in thecommunication system according to the embodiment;

FIG. 10 is a conceptual schematic illustrating a visual informationmanagement table;

FIG. 11 is a conceptual schematic illustrating a relay device managementtable;

FIG. 12 is a conceptual schematic illustrating a terminal authenticationmanagement table;

FIG. 13 is a conceptual schematic illustrating a terminal statusmanagement table;

FIG. 14 is a conceptual schematic illustrating a destination listmanagement table;

FIG. 15 is a conceptual schematic illustrating a session managementtable;

FIG. 16 is a sequence chart illustrating a process of preparing forinitiation of a call between terminals;

FIG. 17 is a flowchart illustrating a process of selecting a dedicatedterminal function or a non-dedicated terminal function;

FIG. 18 is a conceptual schematic illustrating a communication functionselecting screen;

FIG. 19 is a flowchart illustrating a process of displaying adestination list;

FIG. 20 is a conceptual schematic illustrating a destination list;

FIG. 21 is a conceptual schematic illustrating another example of thefunction selecting screen; and

FIG. 22 is a conceptual schematic illustrating another example of thedestination list.

BEST MODE(S) FOR CARRYING OUT THE INVENTION

An embodiment of the present invention will now be explained withreference to FIGS. 1 to 20.

Overall Configuration According to Embodiment

FIG. 1 is a general schematic of a communication system according to theembodiment. As illustrated in FIG. 1, this communication system 1includes a plurality of communication terminals (10 aa, 10 ab, . . . ),a plurality of displays (120 aa, 120 ab, . . . ) for the respectivecommunication terminals (10 aa, 10 ab, . . . ), a plurality of relaydevices (30 a, 30 b, 30 c), a communication management system 50, aprogram providing system 90, and a maintenance system 100. By allowingimage data and audio data, which are examples of communication data(call data), to be exchanged over the communication system 1, ateleconference or the like can be held across remote locations. Aplurality of routers (70 a, 70 b, 70 c, 70 d, 70 ab, 70 cd) selects themost optimal route for communication data.

The communication terminals (10 aa, 10 ab, 10 ac, . . . ), the relaydevice 30 a, and the router 70 a are connected communicatively over alocal area network (LAN) 2 a. The communication terminals (10 ba, 10 bb,10 bc, . . . ), the relay device 30 b, and the router 70 b are connectedcommunicatively over a LAN 2 b. The LAN 2 a and the LAN 2 b areconnected communicatively over a dedicated line 2 ab including therouter 70 ab. The LAN 2 a, the LAN 2 b, and the dedicated line 2 ab aredeployed in a given region X. An example of the region X is Japan, andthe LAN 2 a is deployed in an office in Tokyo, and the LAN 2 b isdeployed an office in Osaka, for example.

The communication terminals (10 ca, 10 cb, 10 cc, . . . ), the relaydevice 30 c, and the router 70 c are connected communicatively over aLAN 2 c. The communication terminals 10 d (10 da, 10 db, 10 dc, . . . ),the relay device 30 d, and the router 70 d are connected communicativelyover a LAN 2 d. The LAN 2 c and the LAN 2 d are connectedcommunicatively over a dedicated line 2 cd including the router 70 cd.The LAN 2 c, the LAN 2 d, and the dedicated line 2 cd are deployed in agiven region Y. An example of the region Y is the United States, and theLAN 2 c is deployed in an office in New York, and the LAN 2 d isdeployed in an office in Washington D.C., for example. The region X andthe region Y are connected communicatively over an Internet 2 i via therespective routers (70 ab, 70 cd).

In the explanation below, the “communication terminal” is simplyreferred to as a “terminal”, and the “communication management system”is simply referred to as a “management system”. Any one of the terminals(10 aa, 10 ab, . . . ) is referred to as a “terminal 10”, and any one ofthe displays (120 aa, 120 ab, . . . ) is referred to as a “display 120”.Any one of the relay devices (30 a, 30 b, 30 c) is referred to as a“relay device 30”. A terminal serving as a requestor requesting to starta teleconference is referred to as a “request source terminal”. Adestination (terminal to which data is to be relayed) that is arequested terminal is referred to as a “destination terminal”. Any oneof the routers (70 a, 70 b, 70 c, 70 d, 70 ab, 70 cd) is referred to asa “router 70”.

The management system 50, the program providing system 90, and themaintenance system 100 are connected to the Internet 2 i. The managementsystem 50, the program providing system 90, and the maintenance system100 may be deployed in the region X or in the region Y, or may bedeployed in any region other than these locations.

In the embodiment, a communication network 2 according to the embodimentincludes the LAN 2 a, the LAN 2 b, the dedicated line 2 ab, the Internet2 i, the dedicated line 2 cd, the LAN 2 c, and the LAN 2 d. Thecommunication network 2 may include some wirelessly communicating parts,e.g., parts communicating over Wireless Fidelity (WiFi) or Bluetooth(registered trademark), as well as those communicating over the wire.

In FIG. 1, a set of four numbers indicated below each of the terminals10, each of the relay devices 30, the management system 50, each of therouters 70, the program providing system 90, and the maintenance system100 represents a general Internet protocol (IP) address that is based onthe Internet Protocol version 4 (IPv4), in a simplified manner. The IPaddress of the terminal 10 aa is “1.2.1.3”, for example. The IPv6 may beused instead of the IPv4, but the IPv4 is used as an example, tosimplify the explanation.

Each of the terminals 10 may be used to achieve communication within thesame room, communication between an outdoor location and an indoorlocation, or communication between an outdoor location and anotheroutdoor location, in addition to communication between offices orcommunication between different rooms in the same office. When theterminals 10 are used outdoor, the terminals 10 communicates with eachother wirelessly, e.g., over a cellular network.

Each of the terminals 10 illustrated in FIG. 1 is a terminal thatexchanges communication data to enable communication between users. Anexample of the terminal 10 is a teleconference terminal. The terminal 10exchanges communication data using a given communication system (asignaling protocol for connecting to and disconnecting from adestination of communication and an encoding protocol for encapsulatingcommunication data (call data) in an IP packet).

Examples of the signaling protocol include (1) the Session InitiationProtocol (SIP), (2) H.323, (3) an SIP extension, (4) an instantmessenger protocol, (5) a protocol using a MESSAGE method defined in theSIP, (6) the Internet Relay Chat (IRC) protocol, and (7) an instantmessenger protocol extension. Among these examples, (4) the instantmessenger protocol is a protocol used in (4-1) the Extensible Messagingand Presence Protocol (XMPP), or (4-2) ICQ (registered trademark), AOLInstant Messenger (AIM) (registered trademark), or Skype (registeredtrademark). An example of (7) an instant messenger protocol extensionincludes Jingle.

Among these terminals 10, a terminal 10 using a communication system inwhich the instant messenger protocol (or the instant messenger protocolextension) is used as a signaling protocol and H.264 Scalable VideoCoding (SVC) is used as the encoding protocol, for example, is referredto as a “dedicated terminal”. Among these terminals 10, a terminal 10using a communication system that uses a different signaling protocoland encoding protocol from those used in a dedicated terminal arereferred to as a “non-dedicated terminal”. In the embodiment, asexamples of two terminals operating on different communicationprotocols, a “dedicated terminal” is explained to be a terminalmanufactured, sold, or managed by a particular company, and a“non-dedicated terminal” is explained to be a terminal manufactured,sold, or managed by a company other than the particular company. Suchexamples are used in the description of the embodiment because terminalsmanufactured, sold, or managed by different companies often usedifferent communication systems. Alternatively, as examples of such twoterminals operating on different communication protocols, a “dedicatedterminal” may be a terminal manufactured or sold later in time, and a“non-dedicated terminal” may be a terminal manufactured or sold earlierin time, among those manufactured or sold by the same company. A dualcodec terminal having the dedicated terminal function and thenon-dedicated terminal function establishes communication using anencoding system that is the same as that used by a peer by starting oneof the dedicated terminal function and the non-dedicated terminalfunction. In other words, by starting the dedicated terminal function, adual codec terminal can communicate with a dedicated terminal using thesame encoding protocol. By starting the non-dedicated terminal function,a dual-codec terminal can communicate with the non-dedicated terminalusing the same encoding protocol.

Each of the relay devices 30 is a computer system that relayscommunication data between the terminals 10. The management system 50 isa computer system that centrally manages authentications of log-inperformed by the terminals 10, the operations status and thecommunication status of the terminals 10, a destination list, and thecommunication status of the relay devices 30. An image represented bythe image data may be a moving image, a still image, or both.

The program providing system 90 is a computer system that providescomputer programs used by the terminals 10, the relay devices 30, themanagement system 50, and the maintenance system 100, respectively, tothe terminals 10, the relay devices 30, the management system 50, andthe maintenance system 100, respectively, over the communication network2.

The maintenance system 100 is a computer system that maintains, manages,or services at least one of the terminals 10, the relay devices 30, themanagement system 50, and the program providing system 90. For example,when the maintenance system 100 is deployed in a domestic location, andthe terminals 10, the relay devices 30, the management system 50, or theprogram providing system 90 are deployed in an oversea location, themaintenance system 100 remotely performs maintenance such asmaintaining, managing, and servicing at least one of the terminals 10,the relay devices 30, the management system 50, and the programproviding system 90 over the communication network 2. The maintenancesystem 100 also performs maintenance such as managing unit numbers,serial numbers, customers, the history of maintenance and inspections,and the history of failures in at least one of the terminals 10, therelay devices 30, the management system 50, and the program providingsystem 90, not over the communication network 2.

A first communication pattern for enabling communication between the twoterminals 10 will now be explained with reference to FIGS. 2 and 3. FIG.2 is a conceptual schematic illustrating communications exchanged whencommunication is established between communication terminals having adedicated terminal function. The terminals 10 include some dedicatedterminals, some non-dedicated terminals, and some dual codec terminalshaving a dedicated terminal function (an example of a firstcommunication function) and a non-dedicated terminal function (anexample of a second communication function). A non-dedicated terminalherein means a terminal operating on a signaling protocol and anencoding protocol that are different from those used on the dedicatedterminal, as mentioned earlier. A non-dedicated terminal function meansa terminal function operating on the same signaling protocol as thededicated terminal function but on a different encoding protocol fromthe dedicated terminal function.

Among these terminals, only a dedicated terminal and a terminal runningthe dedicated terminal function are used in the communication system 1executing the first communication pattern, as illustrated in FIG. 2.Illustrated in FIG. 2 is an example in which the request source terminalis a dual codec terminal 10 that is running a dedicated terminalfunction. The destination terminal is a dedicated terminal.

The communication system 1 exchanges communication data over acommunication system that uses the instant messenger protocol (or theinstant messenger extension protocol) as a signaling protocol and H.264Scalable Video Coding (SVC) as an encoding protocol, for example.Specifically, as illustrated in FIG. 2, in the communication system 1, amanagement communication session sei for exchanging various types ofmanagement information is established between the request sourceterminal and the destination terminal via the management system 50. Thecommunication session sei also serves as a signaling session.

Established between the request source terminal running the dedicatedterminal function and the relay device 30 is a first communicationsession sed1 for exchanging four types of communication data includinghigh-resolution image data, moderate-resolution image data,low-resolution image data, and audio data over the SVC encodingprotocol. Established between the relay device 30 and the destinationterminal is a second communication session sed2 for exchanging fourtypes of communication data including high-resolution image data,moderate-resolution image data, low-resolution image data, and audiodata over the SVC encoding protocol in the same manner.

The resolutions of the images in the image data handled in the firstcommunication pattern illustrated in FIG. 2 will now be explained withreference to FIG. 3. FIG. 3 is a conceptual schematic illustrating theimage qualities of image data exchanged according to the SVC protocolillustrated in FIG. 2.

Exchanged is data of a low-resolution image having 160 pixelshorizontally and 120 pixels vertically and used as a base imageillustrated in FIG. 3(a), a moderate-resolution image having 320 pixelshorizontally and 240 pixels vertically illustrated in FIG. 3(b), and ahigh-resolution image having 640 pixels horizontally and 480 pixelsvertically illustrated in FIG. 3(c). Among these types of image data,when the image data is transferred over a narrowband path, thelow-quality image data including a low-resolution image data which is abase image is relayed by the relay device 30. When the bandwidth isrelatively broad, the low-resolution image data which is the base imageand the moderate-quality image data including moderate-resolution imagedata are relayed by the relay device 30. When the bandwidth is highlybroad, the low-resolution image data having the base image quality, themoderate-resolution image data, and the high-quality image dataincluding high-resolution image data are relayed by the relay device 30.

A second communication pattern for establishing communication betweenthe two terminals 10 will be explained with reference to FIGS. 4 and 5.FIG. 4 is a conceptual schematic illustrating communications exchangedwhen communication is established between terminals having anon-dedicated terminal function.

Only a non-dedicated terminal and a terminal running the non-dedicatedterminal function are used in a communication system 1′ executing thesecond communication pattern, as illustrated in FIG. 4, and cannot beused in the communication system 1 executing the first communicationpattern illustrated in FIG. 2 because a non-dedicated terminal and aterminal running the non-dedicated terminal function use a differentcommunication system from that used by a dedicated terminal and adedicated terminal function. Illustrated in FIG. 4 is an example inwhich the request source terminal is a dual codec terminal running anon-dedicated terminal function, and the destination terminal is anon-dedicated terminal.

The communication system 1′ exchanges communication data over acommunication system that uses an instant messenger protocol (or aninstant messenger extension protocol) as a signaling protocol, which isthe same as that used in the first communication pattern, and H.264Advanced Video Coding (AVC), which is a protocol different from thatused in the first communication pattern, as an encoding protocol for therequest source terminal. Specifically, as illustrated in FIG. 4, amanagement communication session sei1 for exchanging various types ofmanagement information is established between the request sourceterminal and the management system 50 in the communication system P. Thecommunication session sei1 also serves as a signaling session.Furthermore, when a non-dedicated terminal function is running on therequest source terminal, the encoding protocol is converted from the SVCto the AVC.

Established between the management system 50 and the destinationterminal is a communication session sei2 for signaling for thenon-dedicated terminal, and a different signaling protocol is used fromthat used with the request source terminal. The SIP or H.323 is used asa signaling protocol, for example. In such a case, because the requestsource terminal and the destination terminal use different signalingprotocols, the management system 50 converts the signaling protocols.Specifically, when the request source terminal is running thenon-dedicated terminal function, the management system 50 converts datarelated to signaling based on the conversion rule data used forconverting the signaling protocols, and performs the signaling. Theencoding protocol used by the destination terminal (non-dedicatedterminal) is the AVC, which is the same as that on the request sourceterminal running the non-dedicated terminal function.

Established between the request source terminal and the destinationterminal is a communication session sed for exchanging communicationdata. The communication session sed may be established directly betweenthe request source terminal and the destination terminal, or may beestablished via the relay device.

The resolution of the images in the image data handled in the secondcommunication pattern illustrated in FIG. 4 will now be explained withreference to FIG. 5. FIG. 5 is a conceptual schematic illustrating theimage quality of image data exchanged with the AVC protocol illustratedin FIG. 4. As illustrated in FIG. 5, exchanged is a single type of imagedata having 320 pixels horizontally and 240 pixels vertically.

Hardware Configurations According to Embodiment

Hardware configurations according to the embodiment will now beexplained. FIG. 6 is an external view of the communication terminalaccording to the embodiment. As illustrated in FIG. 6, the terminal 10includes a housing 1100, an arm 1200, and a camera housing 1300. Amongthese components, an air inlet surface having a plurality of air inletsnot illustrated are provided on the front wall 1110 of the housing 1100,and an air outlet surface 1121 having a plurality of air outlets isprovided on the rear wall 1120 of the housing 1100. These surfacesallows the air behind the terminal 10 to be collected via the air inletsurface by driving a cooling fan provided inside of the housing 1100,and to be discharged from the air outlet surface 1121 to the rear sideof the terminal 10. On the right wall 1130 of the housing 1100, a soundcollecting opening 1131 is provided so that sound such as a voice, somesound, and a noise can be collected by an internal microphone 114, whichwill be described later.

An operation panel 1150 is provided on the right wall 1130 of thehousing 1100. The operation panel 1150 is provided with a plurality ofoperation buttons (108 a to 108 e) which will be described later, apower switch 109 which will be described later, an alarm lamp 119 whichwill be described later, and an audio output surface 1151 having aplurality of audio output holes through which the sound from an internalspeaker 115 which will be described later is output. On the left wall1140 of the housing 1100, a receptacle 1160 as a recess for receivingthe arm 1200 and the camera housing 1300 is provided. Provided on theright wall 1130 of the housing 1100 are a plurality of connectors (1132a to 1132 c) for electrically connecting cables to an external deviceconnecting I/F 118 which will be described later. Provided on left wall1140 of the housing 1100 is a connector not illustrated for electricallyconnecting a cable 120 c for the display 120 to the external deviceconnecting I/F 118 which will be described later.

In the description hereunder, the term “operation button 108” is used toindicate any one of the operation buttons (108 a to 108 e), and the term“connector 1132” is used to indicate any one of the connectors (1132 ato 1132 c).

The arm 1200 is attached to the housing 1100 via a torque hinge 1210,and the arm 1200 is provided in a manner vertically rotatable withrespect to the housing 1100 within a tilt angle θ₁ of 135 degrees. FIG.6 illustrates a configuration at a tilt angle θ₁ of 90 degrees. Thecamera housing 1300 is provided with an internal camera 112, which willbe described later, to allow the image of users, documents, or a room tobe captured. The camera housing 1300 is provided with the torque hinge1310. The camera housing 1300 is attached to the arm 1200 via the torquehinge 1310. The camera housing 1300 is attached to the arm 1200 via thetorque hinge 1310, and the camera housing 1300 is configured in a mannerhorizontally and vertically rotatable with respect to the arm 1200within a pan angle θ₂ of ±180 degrees when the position illustrated inFIG. 6 is 0 degrees, and within a tilt angle θ₃ of ±45 degrees.

The relay device 30, the management system 50, the program providingsystem 90, and the maintenance system 100 all have the external view ofa general server computer. Therefore, descriptions of the external viewsthereof are omitted herein.

FIG. 7 is a schematic of a hardware configuration of the terminalaccording to the embodiment. As illustrated in FIG. 7, the terminal 10according to the embodiment includes a central processing unit (CPU) 101that controls the entire operations of the terminal 10, a read-onlymemory (ROM) 102 storing therein computer programs such as an initialprogram loader (IPL) used in driving the CPU 101, a random access memory(RAM) 103 used as a working area for the CPU 101, a flash memory 104storing therein computer programs for the terminal 10 and various typesof data such as image data and audio data, a solid state drive (SSD) 105that controls reading and writing of various types of data from and tothe flash memory 104 under the control of the CPU 101, a media drive 107that controls reading and writing (storing) of data to a recordingmedium 106 such as a flash memory, the operation buttons 108 that isoperated when a destination of the terminal 10 is selected, for example,the power switch 109 for powering ON and OFF the terminal 10, and anetwork interface (I/F) 111 for sending data out to the communicationnetwork 2.

The terminal 10 includes the internal camera 112 for acquiring imagedata by capturing the image of a subject under the control of the CPU101, an imaging element I/F 113 for controlling driving of the camera112, an internal microphone 114 for collecting sound, the internalspeaker 115 for outputting sounds, an audio input/output I/F 116 thatprocesses inputs and outputs of audio signals to and from the microphone114 and the speaker 115 under the control of the CPU 101, a display I/F117 that transmits image data to an externally-connected display 120under the control of the CPU 101, the external device connecting I/F 118for connecting various external devices, the alarm lamp 119 forinforming abnormality in various functions provided to the terminal 10,and a bus line 110 such as an address bus and a data bus forelectrically connecting the components listed above, as illustrated inFIG. 5.

The display 120 is a display unit configured as a liquid crystal displayor an organic electroluminescence display for displaying an image of asubject or an operation screen. The display 120 is connected to thedisplay I/F 117 over the cable 120 c. The cable 120 c may be a cable foranalog, red, green, and blue (RGB) (video graphic array (VGA)) signals,a component video cable, a high-definition multimedia interface (HDMI)cable, or a digital video interactive (DVI) cable.

The camera 112 includes a lens, and a solid state imaging element (imagesensor) that electronizes an image (video) of a subject by convertinglight into an electric charge. As the solid state imaging element, acomplementary metal oxide semiconductor (CMOS), a charge coupled device(CCD), or the like is used.

An external device such as an external camera, an external microphone,an external speaker, and the like may be electrically connected to theexternal device connecting I/F 118 over a universal serial bus (USB)cable or the like inserted in the connector 1132 on the housing 1100illustrated in FIG. 6. When an external camera is connected, theexternal camera is driven in a manner prioritized over the internalcamera 112 under the control of the CPU 101. Similarly, when an externalmicrophone or an external speaker is connected, the external microphoneor an external speaker is driven in a manner prioritized over theinternal microphone 114 or the internal speaker 115 under the control ofthe CPU 101.

The recording medium 106 is configured removable from the terminal 10.The recording medium 106 is not limited to the flash memory 104, but maybe an electrically erasable and programmable read-only memory (EEPROM),for example, as long as such a recording medium is a nonvolatile memoryfrom and to which data is read and written under the control of the CPU101.

FIG. 8 is a schematic of a hardware configuration of the managementsystem according to the embodiment. The management system 50 includes aCPU 201 that controls the entire operations of the management system 50,a ROM 202 storing therein computer programs such as an IPL used indriving the CPU 201, a RAM 203 used as a working area for the CPU 201, ahard disk (HD) 204 storing therein various types of data such ascomputer programs for the management system 50, a hard disk drive (HDD)205 that controls reading and writing of various types of data from andto the HD 204 under the control of the CPU 201, a media drive 207 thatcontrols reading and writing (storing) of data from and to a recordingmedium 206 such as a flash memory, a display 208 that displays varioustypes of information such as a cursor, a menu, a window, characters, andan image, a network I/F 209 that exchanges data over the communicationnetwork 2, a keyboard 211 provided with a plurality of keys for allowingcharacters, numbers, and various instructions to be entered, a mouse 212for allowing various instructions to be selected or executed, allowingan object to be processed to be selected, and allowing a cursor to bemoved, for example, a compact disk read-only memory (CD-ROM) drive 214that controls reading and writing of various types of data from and to aCD-ROM 213 that is an example of a removable recording medium, and a busline 210 such as an address bus and a data bus for electricallyconnecting the components listed above, as illustrated in FIG. 6.

The relay device 30, the program providing system 90, and themaintenance system 100 all have the same hardware configuration as thatof the management system 50. Therefore, the explanations thereof areomitted herein. The HDs 204 provided to the relay device 30, the programproviding system 90, and the maintenance system 100, respectively, storetherein various types of data such as a computer programs forcontrolling the relay device 30, the program providing system 90, andthe maintenance system 100, respectively.

The computer programs for the terminal 10, the relay device 30, theprogram providing system 90, and the maintenance system 100 may bedistributed in a manner recorded in a computer-readable recording medium(e.g. the recording medium 106) as a file in an installable or anexecutable format. Other examples of the recording medium includes acompact disk recordable (CD-R), a digital versatile disk (DVD), and aBlu-ray disk.

Functional Configurations According to Embodiment

Functional configurations according to the embodiment will now beexplained. FIG. 9 is a functional block diagram of the terminal 10, therelay device 30, and the management system 50 included in thecommunication system 1 according to the embodiment. In FIG. 9, theterminal 10, the relay device 30, and the management system 50 areconnected over the communication network 2 to enable the terminal 10,the relay device 30, and the management system 50 to exchange data.

Functional Configuration of Terminal

The terminal 10 includes a transmitting/receiving unit 11, an operationinput receiving unit 12, a log-in requesting unit 13, an image capturingunit 14, an audio input unit 15 a, an audio output unit 15 b, a displaycontrolling unit 16, a starting unit 17, a destination list creatingunit 18, and a storing/reading processing unit 19. Each of these unitsis a function realized by causing one of the units illustrated in FIG. 7to operate based on an instruction from the CPU 101 following a computerprogram for the terminal 10 that is loaded from the flash memory 104onto the RAM 103.

The terminal 10 has a storage unit 1000 implemented on the RAM 103illustrated in FIG. 7 and the flash memory 104 illustrated in FIG. 7. Avisual information managing data base (DB) 1001 configured as a visualinformation management table, which will be described later, isimplemented on the storage unit 1000. The dedicated terminal applicationfor realizing the dedicated terminal function on the terminal 10 and anon-dedicated terminal application for realizing the non-dedicatedterminal function on the terminal 10 are stored in the storage unit1000.

Visual Information Management Table

FIG. 10 is a conceptual schematic illustrating the visual informationmanagement table. The visual information management table managesoperation status information indicating the operation status of adestination terminal in a manner associated with visual information tobe included in a destination list displayed on the display 120. Visualinformation is an icon having a shape illustrated in FIG. 10, forexample. The management system 50 may transmit the visual informationincluded in the visual information management table when a requestsource terminal requests to log in at Step S22, which will be describedlater. Alternatively, the visual information may be stored in thestorage unit 1000 in the request source terminal before the terminal isshipped from the factory.

The visual information according to the embodiment is classified intofirst visual information visually indicating that the communicationsystem used by the destination terminal is the same as that used by therequest source terminal (dedicated terminal) and second visualinformation visually indicating that the communication system used bythe destination terminal is not same as that used by the request sourceterminal (dedicated terminal) and visually different from the firstvisual information. The first visual information includes visualinformation such as icons indicating that the operation status ison-line (available), on-line (calling), on-line (temporarilyunavailable), or off-line.

The second visual information represents an icon displayed on thedisplay 120 of a request source terminal, when a terminal 10 having bothof a dedicated terminal function and a non-dedicated terminal functioncommunicates with another terminal 10 having both of the dedicatedterminal function and a non-dedicated terminal function, and the requestsource terminal is currently running the dedicated terminal function andthe destination terminal is running the non-dedicated terminal function,for example.

Each Functional Unit in Terminal

Each of the functional units in the terminal 10 will now be explained indetail with reference to FIGS. 7 and 9. While explaining each of thefunctional units in the terminal 10, a relationship with some of theunits illustrated in FIG. 7 that are mainly used in realizing thefunctional unit of the terminal 10 will be explained as well.

The transmitting/receiving unit 11 included in the terminal 10 andillustrated in FIG. 9 is realized by an instruction issued by the CPU101 illustrated in FIG. 7 and the network I/F 111 illustrated in FIG. 7.The transmitting/receiving unit 11 transmits and receives various typesof data (or information) to and from with other terminals, devices, orsystems over the communication network 2. Before initiating a call witha target destination terminal, the transmitting/receiving unit 11 startsreceiving status information of each of the terminals that arecandidates for the destination from the management system 50. The statusinformation not only indicate the operation status (on-line or off-line)of the terminal 10, but also detailed status of the terminal 10, e.g.,the terminal is on-line and is available for receiving a call, theterminal is currently calling, or a user is not seated. In addition tothe operation of status of the terminal 10, status information indicatesvarious types of status, such as a status indicating that the cable 120c is disconnected from the terminal 10, a status indicating that nosound but an image is output, or a status indicating that no sound isoutput (MUTE). The status information includes a status indicating thata non-dedicated terminal function is running, as mentioned earlier.Described below is an example in which the status information indicatesan operation status.

The operation input receiving unit 12 is realized by an instruction fromthe CPU 101 illustrated in FIG. 7, and the operation button 108 and thepower switch 109 illustrated in FIG. 7. The operation input receivingunit 12 receives various inputs from a user. For example, when a userturns ON the power switch 109 illustrated in FIG. 7, the operation inputreceiving unit 12 illustrated in FIG. 9 receives the power-ON, and turnsthe power ON.

The log-in requesting unit 13 is realized by an instruction from the CPU101 illustrated in FIG. 7. The log-in requesting unit 13 is triggered byreceiving the power-ON, and automatically transmits log-in requestinformation requesting to log in from the management system 50 and acurrent IP address of the request source terminal to the managementsystem 50 via the transmitting/receiving unit 11 over the communicationnetwork 2. When the user changes the status of the power switch 109 fromON to OFF, the transmitting/receiving unit 11 is caused to transmit thestatus information indicating that the power is turned OFF to themanagement system 50, and the operation input receiving unit 12 thencompletely shuts the power OFF. In this manner, the management system 50can recognize that the power of the terminal 10 is switched from ON toOFF.

The image capturing unit 14 is realized by an instruction from the CPU101 illustrated in FIG. 7, and the camera 112 and the imaging elementI/F 113 illustrated in FIG. 7. The image capturing unit 14 captures animage of a subject, and outputs the image data acquired by capturing.

The audio input unit 15 a is realized by an instruction from the CPU 101illustrated in FIG. 7 and the audio input/output I/F 116 illustrated inFIG. 7. The audio input unit 15 a receives audio data related to anaudio signal which is a user's voice converted by the microphone 114.The audio output unit 15 b is realized by an instruction from the CPU101 illustrated in FIG. 7 and the audio input/output I/F 116 illustratedin FIG. 7. The audio output unit 15 b outputs an audio signal related toaudio data, and causes the speaker 115 to output sound.

The display controlling unit 16 is realized by an instruction from theCPU 101 illustrated in FIG. 7 and the display I/F 117 illustrated inFIG. 7. The display controlling unit 16 controls to combine pieces ofimage data at different resolutions and to transmit the image data thuscombined to the display 120, in a manner to be described later. Thedisplay controlling unit 16 is also capable of transmitting informationof a destination list received from the management system 50 to thedisplay 120, and causing the display 120 to display the destinationlist.

The display controlling unit 16 searches visual information managementtable (see FIG. 10) using the operation status information received fromthe management system 50 via the transmitting/receiving unit 11 as asearch key, extracts matching visual information, and causes the display120 on the local terminal 10 to display the visual information includedin the destination list.

The starting unit 17 determines if any call initiating request isreceived by the transmitting/receiving unit 11 from another dedicatedterminal (or another terminal running the dedicated terminal function).The starting unit 17 also starts one of the dedicated terminal functionand the non-dedicated terminal function. The starting unit 17 also stopsthe dedicated terminal function or the non-dedicated terminal functioncurrently running.

The destination list creating unit 18 creates and updates a destinationlist in which an icon is used to indicate the status of each of thedestination candidates, as illustrated in FIG. 20, based on destinationlist information and status information, which is to be described later,of each of the terminals 10 that are destination candidates receivedfrom the management system 50.

The storing/reading processing unit 19 is caused to execute by aninstruction from the CPU 101 illustrated in FIG. 7 and by the SSD 105illustrated in FIG. 7, or realized by an instruction from the CPU 101.The storing/reading processing unit 19 performs a process of storingvarious types of data in the storage unit 1000, and a process of readingvarious types of data stored in the storage unit 1000. A terminalidentification (ID) for identifying a terminal 10, a password, and thelike are stored in the storage unit 1000. Image data and audio datareceived every time a call is established with a destination terminal isalso stored in the storage unit 1000 in a manner overwriting previousdata every time such data is received. An image is displayed on thedisplay 120 based on the image data before being overwritten, and soundis output from the speaker 115 based on the audio data before beingoverwritten.

A terminal ID and a relay device ID to be described later according tothe embodiment are identification information such as a language, acharacter, a symbol, or various types of marks used as a uniqueidentification of the terminal 10 and the relay device 30, respectively.A terminal ID and a relay device ID may be identification informationconsisting of a combination of at least two of a language, a character,a symbol, and various marks described above.

Functional Units in Relay Device

The relay device 30 includes a transmitting/receiving unit 31 and a dataquality changing unit 32. Each of these units is a function or a unitrealized by causing one of the units illustrated in FIG. 8 to operatebased on an instruction from the CPU 201 following a computer programfor the relay device 30 that is loaded from the HD 204 onto the RAM 203.

Each Functional Unit in Relay Device

Each of the functional units in the relay device 30 will now beexplained in detail. While explaining each of the functional units inthe relay device 30, a relationship with some of the units illustratedin FIG. 8 that are mainly used in realizing the functional unit of therelay device 30 will be explained as well.

The transmitting/receiving unit 31 in the relay device 30 illustrated inFIG. 9 is realized by an instruction from the CPU 201 illustrated inFIG. 8, and the network I/F 209 illustrated in FIG. 8. Thetransmitting/receiving unit 31 transmits and receives various types ofdata (or information) to and from other terminals, devices, or systemsover the communication network 2. The transmitting/receiving unit 31enables the relay device 30 to relay communication data exchangedbetween the terminals 10.

The transmitting/receiving unit 31 also transmits session initiatinginformation for giving an instruction to initiate a communicationsession (first communication session sed1) to a destination identifiedby the IP address of a request source terminal, among the IP addressesreceived by the transmitting/receiving unit 31. Thetransmitting/receiving unit 31 also transmits session initiatinginformation for initiating a communication session (second communicationsession) and the IP address of the destination terminal to thedestination identified by the IP address, among the IP addressesreceived by the transmitting/receiving unit 31.

The data quality changing unit 32 is realized by an instruction from theCPU 201 illustrated in FIG. 8. The data quality changing unit 32 changesthe image quality of the image data received from a source terminal.This functional unit enables the relay device 30 to reduce the imagequality of the image data to be relayed when there is a delay in theimage data received by the terminal 10, e.g., due to a congestion in thecommunication network 2, so that the delay is compensated. For example,the delay is compensated by stopping to relay the high-resolution imagedata (see FIG. 3(c)) among the image data of three different imagequalities, for example, when a delay occurs in receptions of the imagedata.

Functional Configuration of Management System

The management system 50 includes a transmitting/receiving unit 51, aterminal authenticating unit 52, a status managing unit 53, anextracting unit 54, a determining unit 55, a session managing unit 56, aconverting unit 57, and a storing/reading processing unit 59. Each ofthese functions is a function or a unit realized by causing one of theunits illustrated in FIG. 8 to operate based on an instruction from theCPU 201 following a computer program for the management system 50 thatis loaded from the HD 204 onto the RAM 203. The management system 50also includes a storage unit 5000 implemented by the HD 204 illustratedin FIG. 8. Stored in the storage unit 5000 is frame data for adestination list, which will be described later, and conversion ruledata that is used in converting signaling protocols.

Relay Device Management Table

FIG. 11 is a conceptual schematic illustrating a relay device managementtable. Implemented in the storage unit 5000 is a relay device managementDB 5001 that is implemented as a relay device management table, asillustrated in FIG. 11. The relay device management table manages, foreach relay device ID corresponding to each of the relay devices 30, theoperation status of the relay device 30, the time and the date at whichthe status information indicating the operation status is received bythe management system 50, the IP address of the relay device 30, and themaximum data communication rate (megabits per second) in the relaydevice 30, in an associated manner. For example, the relay devicemanagement table illustrated in FIG. 11 indicates, for the relay device30 a having a relay device ID “111a”, that the operation status is“on-line”, the status information is received by the management system50 at “2011.11.10.13:00”, the IP address of the relay device 30 a is“1.2.1.2”, and the maximum data communication rate in the relay device30 a is 100 megabits per second.

Terminal Authentication Management Table

FIG. 12 is a conceptual schematic illustrating a terminal authenticationmanagement table. Implemented on the storage unit 5000 is a terminalauthentication management DB 5002 that is implemented as a terminalauthentication management table, as illustrated in FIG. 12. The terminalauthentication management table manages an authentication password and aterminal ID corresponding to each of the terminals 10 managed by themanagement system 50, in an associated manner. For example, the terminalauthentication management table illustrated in FIG. 12 indicates thatthe terminal ID of the terminal 10 aa is “01aa”, and the password is“aaaa”.

Terminal Status Management Table

FIG. 13 is a conceptual schematic illustrating a terminal statusmanagement table. Implemented on the storage unit 5000 is a terminalstatus management DB 5003 that is implemented as a terminal statusmanagement table, as illustrated in FIG. 13. The terminal statusmanagement table manages, for each of the terminal IDs corresponding toeach of the terminals 10, a destination name that is used when theterminal 10 is designated as a destination, the operation status of theterminal 10, the time and the date at which log-in request information,which will be described later, is received by the management system 50,and the IP address of the terminal 10, in an associated manner. Forexample, the terminal status management table illustrated in FIG. 13indicates that the terminal 10 aa with a terminal ID “01aa” has aterminal name “terminal AA, Tokyo Office, Japan”, an operation status“on-line (available)”, the log-in request information is received by themanagement system 50 at “2011.11.10.13:40”, and the IP address of theterminal 10 aa is “1.2.1.3”.

The terminal status management table does not manage the terminalinformation such as the terminal IDs, the terminal names, the operationstatuses, the receiving time and date, and the IP addresses of thenon-dedicated terminals 10 (in other words, terminals other than theterminals having the dedicated terminal function and dedicatedterminals) because such terminal information is out of the scope ofmanagement.

Destination List Management Table

FIG. 14 is a conceptual schematic illustrating a destination listmanagement table. Implemented on the storage unit 5000 is a destinationlist management DB 5004 that is implemented as a destination listmanagement table, as illustrated in FIG. 14. The destination listmanagement table manages terminal IDs of all of the destinationterminals registered as a destination candidate and the terminal ID of arequest source terminal requesting a call to be initiated, in anassociated manner. For example, the destination list management tableillustrated in FIG. 14 indicates that a request source terminal with aterminal ID “01aa” (terminal 10 aa) can request a call from destinationterminal candidates including a terminal 10 ab with a terminal ID“01ab”, a terminal 10 ba with a terminal ID “01ba”, and a terminal 10 bbwith a terminal ID “01bb”. The destination terminal candidates areupdated by adding or deleting a terminal ID in response to a request foradding or deleting the terminal issued by a request source terminal tothe management system 50. The destination list management table (seeFIG. 14) does not manage the terminal IDs of the non-dedicated terminalsbecause such terminal IDs are out of the scope of management in the samemanner as the terminal status management table.

Session Management Table

FIG. 15 is a conceptual schematic illustrating a session managementtable. Implemented on the storage unit 5000 is a session management DB5005 that is implemented as a session management table, as illustratedin FIG. 15. The session management table manages the relay device ID ofa relay device 30 used in relaying communication data (image data andaudio data), the terminal ID of the request source terminal, theterminal ID of the destination terminal, the receiving delay time(milliseconds) by which the image data is received by the destinationterminal, and the time and the date at which delay time informationindicating the delay time and transmitted from the destination terminalis received by the management system 50, in an associated manner.

For example, the session management table illustrated in FIG. 15indicates that a relay device 30 a (relay device ID “111a”) relays imagedata and audio data between a request source terminal with a terminal ID“01aa” (terminal 10 aa) and a destination terminal with a terminal ID“01ca” (terminal 10 ca), and the delay time of the image data at thedestination terminal (terminal 10 ca) as of “2011.11.10.14:00” is 200milliseconds. When communication is to be established between twoterminals 10, the time and the date at which the delay time informationis received may be managed based on the delay time information receivedfrom the request source terminal, not the delay time informationreceived from the destination terminal. When communication is to beestablished between three or more terminals 10, the time and the date atwhich the delay time information is received is managed based on thedelay time information received from the terminal 10 receiving the imagedata and the audio data.

Each Functional Unit in Management System

Each of the functional units in the management system 50 will now beexplained in detail. While explaining each of the functional units inthe management system 50, a relationship with some of the unitsillustrated in FIG. 8 that are mainly used in realizing the functionalunit of the management system 50 will be explained as well.

The transmitting/receiving unit 51 is caused to execute by aninstruction from the CPU 201 illustrated in FIG. 8 and the network I/F209 illustrated in FIG. 8. The transmitting/receiving unit 51 transmitsand receives various types of data (or information) to and from otherterminals, devices, or systems over the communication network 2.

The terminal authenticating unit 52 is realized by an instruction fromthe CPU 201 illustrated in FIG. 8. The terminal authenticating unit 52authenticates a terminal by searching the terminal authenticationmanagement table (see FIG. 12) using the terminal ID and the passwordincluded in the log-in request information received via thetransmitting/receiving unit 51 as a search key, and by determining if amatching terminal ID and password are managed in the terminalauthentication management table.

The status managing unit 53 is realized by an instruction from the CPU201 illustrated in FIG. 8. To manage the operation status of a requestsource terminal requesting to log in, the status managing unit 53manages the terminal ID of the request source terminal, the operationstatus of the request source terminal, the time and the date at whichthe log-in request information is received by the management system 50,and the IP address of the request source terminal in the terminal statusmanagement table (see FIG. 13) in an associated manner. When a userswitches the power switch 109 of the terminal 10 from ON to OFF, thestatus managing unit 53 switches the on-line operation status to theoff-line status in the terminal status management table (see FIG. 13),based on the status information indicating that the power is turned OFFreceived from the terminal 10.

The extracting unit 54 is realized by an instruction from the CPU 201illustrated in FIG. 8. The extracting unit 54 searches correspondingmanagement DB implemented on the storage unit 5000 using various typesof a search key, and extracts data (information) corresponding to thesearch key as a search result.

For example, the extracting unit 54 searches the destination listmanagement table (see FIG. 14) using the terminal ID of a request sourceterminal requesting to log in as a key, and extracts terminal IDs of thedestination terminal candidates that are available for communicationwith the request source terminal. The extracting unit 54 then searchesterminal status table (see FIG. 13) using the terminal IDs of thedestination terminal candidates as search keys, and extracts anoperation status for each of the terminal IDs. This process allows theextracting unit 54 to acquire the operation status of a destinationterminal candidate available for communication with a request sourceterminal requesting to log in.

The extracting unit 54 also searches the destination list managementtable (see FIG. 14) using the terminal ID of the request source terminalrequesting to log in as a key, and extracts the terminal ID of anotherrequest source terminal having registered the terminal ID of the requestsource terminal as a destination terminal candidate. The extracting unit54 also acquires operation status of a request source terminalrequesting to log in by searching the terminal status management table(see FIG. 13) using the terminal ID as a search key.

The extracting unit 54 also searches the terminal status managementtable (see FIG. 13) using the terminal ID of a terminal 10 received bythe transmitting/receiving unit 51 as a search key, and extracts the IPaddress of the corresponding terminal 10. The extracting unit 54 alsosearches the terminal status management table (see FIG. 13) using the IPaddress of a destination terminal as a search key, and extracts thecorresponding terminal ID.

The determining unit 55 is realized by an instruction from the CPU 201illustrated in FIG. 8, and determines if the operation status indicatedby the operation status information is “on-line”. If the operationstatus is determined to be “on-line”, the determining unit 55 furtherdetermines that the operation status information can be transmitted to agiven terminal 10. If the determining unit 55 determines that theoperation status is not “on-line”, the determining unit 55 determinesthat the operation status information cannot be transmitted to the giventerminal 10.

The session managing unit 56 is realized by an instruction from the CPU201 illustrated in FIG. 8, and stores and manages the relay device ID ofthe relay device 30 to be used in relaying the communication data, theterminal ID of the request source terminal, the terminal ID of thedestination terminal, a receiving delay time (milliseconds) by which theimage data is received by the destination terminal, and the time and thedate at which the delay time information indicating the delay timetransmitted by the destination terminal is received by the managementsystem 50 in the session management table (see FIG. 15) implemented onthe storage unit 5000 in an associated manner. The session managing unit56 also generates a session ID that is used in establishing acommunication session.

When the operation status corresponding to the terminal ID of therequest source terminal indicates that the non-dedicated terminalfunction has been started in the terminal status management table, theconverting unit 57 performs signaling and conversion of the signalingprotocol received from the request source terminal into a signalingprotocol received from the destination terminal and vice versa, based onthe conversion rule data stored in the storage unit 5000 in advance.

The storing/reading processing unit 59 is executed by an instructionfrom the CPU 201 illustrated in FIG. 8 and the HDD 205 illustrated inFIG. 8, and performs a process of storing various types of data in thestorage unit 5000 and reading various types of data stored in thestorage unit 5000.

Process or Operation According to Embodiment

Explained now with reference to FIGS. 6, 9, and 16 to 20 is an examplein which the terminal 10 having the dedicated terminal function and thenon-dedicated terminal function is a request source terminal. FIG. 16 isa sequence chart illustrating a call initiating request.

As illustrated in FIG. 16, when a user of a dual codec request sourceterminal (terminal 10 aa) turns ON the power switch 109 illustrated inFIG. 6, the operation input receiving unit 12 illustrated in FIG. 9receives the power ON and turns the power ON (Step S21). The log-inrequesting unit 13 is triggered by the reception of the power-ON,automatically transmits log-in request information indicating a log-inrequest from the transmitting/receiving unit 11 to the management system50 over the communication network 2 (Step S22). The log-in requestinformation includes the terminal ID for identifying the terminal 10 aathat is a request source terminal and a password. The terminal ID andthe password are data that is read from the storage unit 1000 via thestoring/reading processing unit 19, and transmitted to thetransmitting/receiving unit 11. When the log-in request information istransmitted from the request source terminal (terminal 10 aa) to themanagement system 50, the management system 50 that is a receiver canrecognize the IP address of the terminal 10 aa that is a transmitter.

The terminal authenticating unit 52 in the management system 50 thensearches the terminal authentication management table (see FIG. 12),using the terminal ID and the password included in the log-in requestinformation received via the transmitting/receiving unit 51 as searchkeys, and authenticates the terminal by determining if the matchingterminal ID and password are managed in the terminal authenticationmanagement table (Step S23). Because the matching terminal ID andpassword are managed by the terminal authenticating unit 52, when alog-in request is determined to be issued by a terminal 10 with a validaccess, the status managing unit 53 stores the operation status and thereceiving time and date at which the log-in request information isreceived in the terminal status management table (see FIG. 13) in amanner associated with the IP address of the terminal 10 aa, for eachrecord indexed with the terminal ID of the terminal 10 aa and thedestination name (Step S24). Through this process, the operation status“on-line”, the receiving time and date “2011.11.10.13:40”, and theterminal IP address “1.2.1.3” are stored in the terminal statusmanagement table in a manner associated with the terminal ID “01aa” andthe destination name.

The transmitting/receiving unit 51 in the management system 50 transmitsauthentication result information indicating the authentication resultacquired by the terminal authenticating unit 52 to the request sourceterminal having requested to log in (terminal 10 aa) over thecommunication network 2 (Step S25). Explained now is a process performedwhen the terminal authenticating unit 52 determines that the terminalhas a valid access in the embodiment.

The extracting unit 54 in the management system 50 searches thedestination list management table (see FIG. 14) using the terminal ID“01aa” of the request source terminal having requested to log in(terminal 10 aa), and extracts terminal IDs of other request sourceterminals having registered the terminal ID “01aa” of the request sourceterminal (terminal 10 aa) as a destination terminal candidate (StepS26). To simplify the explanation, explained below is an example inwhich the terminal ID extracted at Step S26 is the terminal ID “01ba” ofthe terminal 10 ba.

The extracting unit 54 in the management system 50 then searches theterminal status management table (see FIG. 13) using the terminal ID“01aa” of the request source terminal (terminal 10 aa) having requestedto log in as a search key, and extracts the operation status of therequest source terminal having requested to log in (terminal 10 aa)(Step S27).

The transmitting/receiving unit 51 then transmits “terminal statusinformation” including the terminal ID “01aa” of the request sourceterminal (terminal 10 aa) and the operation status informationindicating the operation status of the request source terminal (terminal10 aa) to the terminal 10 ba (Step S28). Through this process, thetransmitting/receiving unit in the terminal 10 ca receives the terminalstatus information. The terminal 10 ba then creates a destination listreflected with the latest operation status of the terminal 10 aa, in thesame manner as the process at Step S28 to be described later, anddisplays the destination list on the display 120 ba.

The request source terminal (terminal 10 aa) then performs a process ofselecting one of the dedicated terminal function and the non-dedicatedterminal function (Step S29). The process of selecting the functionswill now be explained more in detail with reference to FIG. 17. FIG. 17is a flowchart of a process of selecting the dedicated terminal functionor the non-dedicated terminal function.

To begin with, the display controlling unit 16 in the request sourceterminal (terminal 10 aa) displays a function selecting screen 900 onthe display 120 aa as illustrated in FIG. 18 (Step S29-1). FIG. 18 is aconceptual schematic illustrating a communication function selectingscreen. As illustrated in FIG. 18, a function selecting icon 910 (anexample of a first icon) for starting the dedicated terminal functionand a function selecting icon 920 for starting the non-dedicatedterminal function (an example of the second icon) are displayed side byside in the function selecting screen 900. In the lower right side inthe function selecting screen 900, an end icon 990 for ending theprocess of selecting the functions is displayed.

The operation input receiving unit 12 in the request source terminal(terminal 10 aa) determines which one of the function selecting icon 910and the function selecting icon 920 illustrated in FIG. 18 is selectedby the user (Step S29-2). If the operation input receiving unit 12determines that neither one of these icons are selected at Step S29-2,the transmitting/receiving unit 11 further determines if any callinitiating request is received from another dedicated terminal (oranother terminal running the dedicated terminal function) (Step S29-3).If the transmitting/receiving unit 11 determines that no call initiatingrequest is received at Step S29-3 (No), the system control returns toStep S29-1. If the transmitting/receiving unit 11 determines that a callinitiating request is received at Step S29-3 (Yes), the starting unit 17initiates the dedicated terminal function (Step S29-4). Through thisprocess, the terminal 10 aa can start communication as a dedicatedterminal.

At Step S29-2, if the operation input receiving unit 12 determines thatone of the function selecting icon 910 or the function selecting icon920 is selected, the operation input receiving unit 12 determines if thefunction selecting icon 910 for starting the dedicated terminal functionis selected (Step S29-5). If the operation input receiving unit 12determines that the function selecting icon 910 is selected at StepS29-5, the starting unit 17 initiates the dedicated terminal function(Step S29-6). In this case, the terminal 10 aa can start communicationas a dedicated terminal through the process at Steps S41 to S49 to bedescribed later.

If the operation input receiving unit 12 determines that the functionselecting icon 910 is not selected (determines that the functionselecting icon 920 is selected) at Step S29-5, thetransmitting/receiving unit 11 in the request source terminal (terminal10 aa) transmits the terminal status information indicating that thenon-dedicated terminal function is running to the management system 50(Step S29-7). By transmitting the terminal status information, themanagement system 50 is caused to update the operation status of theterminal ID corresponding to the terminal 10 aa in the terminal statusmanagement table to a status indicating that the non-dedicated terminalfunction is running. The starting unit 17 in the request source terminal(terminal 10 aa) then starts the non-dedicated terminal function (StepS29-8). When the request source terminal (terminal 10 aa) functions as anon-dedicated terminal, because the destination list illustrated in FIG.20, which will be described later, is not displayed, the user need toenter address information that allows the location of the destinationterminal to be identified (e.g., the IP address) to designate thedestination. Once the user enters the IP address of the designationterminal (non-dedicated terminal), for example, the operation inputreceiving unit 12 receives the designation of the destination (StepS29-9). Through this process, the request source terminal (terminal 10aa) can start communication as a non-dedicated terminal.

Specifically, the request source terminal transmits a call initiatingrequest addressed to the IP address thus entered to the managementsystem 50, and, because the terminal status management table indicatesthe operation status of the terminal ID of the request source terminalbeing running the non-dedicated terminal function, the management system50 causes the converting unit 57 to convert the call initiating requestthus received into data according to the conversion data rule (that is,data according to the signaling protocol of the non-dedicated terminal).The call initiating request thus converted is transmitted to thedestination terminal (non-dedicated terminal), based on the IP addressreceived from the management system 50. If the destination terminal(non-dedicated terminal) receiving the call initiating request isavailable for communication, the destination terminal responds to themanagement system 50. After the management system 50 coverts theresponse according to the conversion data rule, in the same manner asthe call initiating request, the management system 50 forwards theresponse to the request source terminal. Through such a sequence ofsignaling process, a communication session sed can be establishedbetween the request source terminal and the destination terminal, asillustrated in FIG. 4. In the example illustrated in FIG. 4, because therequest source terminal is running the non-dedicated terminal function,the AVC encoding protocol, which is the same as that used on thedestination terminal (non-dedicated terminal), is used as the encodingprotocol.

At Step S29-9, the IP address is entered by a user. Alternatively, thelocation information of the non-dedicated terminal such as the IPaddress may be stored in the terminal 10 in advance, and made availablefor selection by a user.

The process for initiating communication after the process at Step S29-6illustrated in FIG. 17 will now be explained with reference to FIGS. 19and 20. FIG. 19 is a flowchart illustrating a process of displaying adestination list. FIG. 20 is a conceptual schematic illustrating adestination list.

To begin with, in the request source terminal (terminal 10 aa), uponreceiving the authentication result information indicating a result thatthe request source terminal is determined to have a valid access at StepS25, the transmitting/receiving unit 11 transmits destination listrequesting information requesting a destination list to the managementsystem 50 over the communication network 2 (Step S41). Thetransmitting/receiving unit 51 in the management system 50 then receivesthe destination list requesting information.

The extracting unit 54 in the management system 50 searches thedestination list management table (see FIG. 14) using terminal ID “01aa”of the request source terminal (terminal 10 aa) having requested to login as a search key, and extracts the terminal IDs of the destinationterminal candidates available for communication with the request sourceterminal (terminal 10 aa). The extracting unit 54 then uses the terminalIDs as search keys to search the terminal status management table (seeFIG. 13), and extracts corresponding destination name information (StepS42). To simplify the explanation, explained below is an example inwhich the terminal IDs of a terminal 10 ab, a terminal 10 ba a terminal10 ca, a terminal 10 cb, and the like that are dedicated terminals A areextracted as terminals 10 being the destination terminal candidates.

The extracting unit 54 then reads the frame data of the destination listfrom the storage unit 5000 (Step S43). The transmitting/receiving unit51 then transmits “destination list information (the frame of thedestination list, the terminal IDs, and the destination names)”including the frame of the destination list, and the terminal IDs anddestination name information extracted at Step S42 to the request sourceterminal (terminal 10 aa) (Step S44). The transmitting/receiving unit 11in the request source terminal (terminal 10 aa) receives the destinationlist information.

The storing/reading processing unit 19 in the request source terminal(terminal 10 aa) then stores the destination list information in thestorage unit 1000 (Step S45).

In the manner described above, in the embodiment, instead of managingthe destination list information on each of the terminals 10, themanagement system 50 centrally manages the destination list informationof all of the terminals. Therefore, when a new terminal 10 is started tobe used in the communication system 1, when a terminal 10 currentlybeing used is replaced with a terminal 10 of a new model, or when theappearance of the frame of a destination list is changed, for example,such changes are made centrally on the management system 50, and thework to be done on each of the terminals 10 to change the destinationlist information can be omitted.

In the management system 50, the extracting unit 54 extracts theoperation status of the terminals 10 that are the destination terminalcandidates (Step S46).

The transmitting/receiving unit 51 then transmits the “terminal statusinformation” including the terminal ID “01ca”, which is used as a searchkey at Step S42, and “on-line (available)” which is the operation statusof the destination terminal (terminal 10 ca) to the request sourceterminal (terminal 10 aa) over the communication network 2 (Step S47).The transmitting/receiving unit 51 may transmit the “terminal statusinformation” indicating the terminal ID and the operation status of theterminal (terminal 10 aa) to the request source terminal (terminal 10aa).

The storing/reading processing unit 19 in the request source terminal(terminal 10 aa) sequentially stores the terminal status informationreceived from the management system 50 in the storage unit 1000 (StepS48). In this manner, the request source terminal (terminal 10 aa) canacquire the current operation status of other terminals 10 that areavailable for communication with the request source terminal (terminal10 aa), by receiving the terminal status information of each of thecandidate terminals.

The destination list creating unit 18 in the request source terminal(terminal 10 aa) then creates a destination list 2100 in which thestatuses of the destination candidate terminals 10 are reflected basedon the destination list information and the terminal status informationstored in the storage unit 1000, and the display controlling unit 16displays the destination list 2100, as illustrated in FIG. 20 on thedisplay 120 aa illustrated in FIG. 1 (Step S49). The following processis performed to reflect the statuses of the terminals 10 to thedestination list. The destination list creating unit 18 searches thevisual information management table (see FIG. 10) based on the terminaloperation status information included in the terminal statusinformation, and extracts the corresponding visual information. Thedestination list creating unit 18 then assigns the visual informationthus extracted to the frame of the destination list in the destinationlist information, for each of the terminal IDs and the destination namesincluded in the destination list information. In FIG. 20, the operationstatuses of four destination candidates (2110, 2120, 2130, 2140) areindicated by icons, which are examples of the visual information. Inthis manner, the user can recognize the operation statuses of thedestination candidates before initiating communication.

Displayed at the bottom of the destination list 2100 is a return icon2300 (an example of a third icon) for returning back to the functionselecting screen 900 illustrated in FIG. 18. On the right side of thedestination list 2100, a scroll bar 2200 is displayed. When a user movesthe scroll bar 2200 up and down, the visual information displayed in thedestination list is caused to move up and down.

Main Advantages Achieved by Embodiment

As explained above, according to the embodiment, a plurality of types ofcommunication functions can be used advantageously, even when thecommunication functions use communication systems in which the signalingprotocols are the same but encoding protocols are different.

Supplement to Embodiment

In the embodiment, as illustrated in FIG. 18, a selection is made fromtwo functions, but the present invention is not limited thereto, and aselection may be made from three or more functions.

In the embodiment, explained with reference to FIGS. 18 and 20 are iconsdisplayed on the display 120 of the teleconference terminal which is anexample of the communication terminal, but various types of icons may bedisplayed on a display 120′ of a terminal 10′ such as a smartphone, asillustrated in FIGS. 21 and 22. FIG. 21 is a conceptual schematicillustrating another example of the function selecting screen. FIG. 22is a conceptual schematic illustrating another example of thedestination list.

In FIGS. 21 and 22, a terminal 10′, an operation button 108′, amicrophone 114′, a speaker 115′, a display 120′, a function selectingicon 910′, and a function selecting icon 920′ correspond to the terminal10, the operation button 108, the microphone 114, the speaker 115, thedisplay 120, the function selecting icon 910, and the function selectingicon 920 on the teleconference terminal, respectively.

In FIG. 22, a destination list 2100′, destination candidates (2110′,2120′, 2130′, 2140′), a scroll bar 2200′, and a return icon 2300′correspond to the destination list 2100, the destination candidates(2110, 2120, 2130, 2140), the scroll bar 2200, and the return icon 2300,respectively, on the teleconference terminal.

The various types of icons illustrated in FIGS. 10, 18, and 20 mayinclude characters or symbols in addition to the pictograms.

Furthermore, explained in the embodiment is an example in which imagedata and audio data are exchanged, but the present invention is notlimited thereto, and only the audio data may be exchanged. Such aconfiguration would be incapable of achieving the advantages of theteleconference system, but can realize a conference only using voice, inthe same manner as an ordinary telephone.

Each of the relay device 30, the management system 50, the programproviding system 90, and the maintenance system 100 according to theembodiment may be implemented on a single computer, or may bedistributed among a plurality of computers assigned with some of theunits (functions or means) described above. When the program providingsystem 90 is configured as a single computer, the computer programtransmitted by the program providing system 90 may be divided into aplurality of modules before transmitting, or may be transmitted withoutbeing divided. Furthermore, when the program providing system 90 isbuilt on a plurality of computers, the computer program can betransmitted in a manner divided into a plurality of modules from each ofthe computers.

Furthermore, a recording medium such as a CD-ROM storing therein thecomputer program according to the embodiment, the HD 204 storing thereinthe computer program, and the program providing system 90 including theHD 204 may be made available domestically or to the overseas as acomputer program product.

Furthermore, the receiving time and date is managed in FIGS. 11, 13, and15, but the present invention is not limited thereto, and at least thereceiving time, among the receiving time and date, may be managed.

Furthermore, in the embodiment, the IP address of the relay device ismanaged in FIG. 11, and the IP address of the terminal is managed inFIG. 13, but the present invention is not limited thereto, and the fullyqualified domain name (FQDN) of the relay device 30 or of the terminal10 may be managed, as long as such a name serves as destinationinformation that allows the relay device 30 to be identified on thecommunication network 2 and the terminals 10 to be identified on thecommunication network 2. In such a case, a known domain name system(DNS) server acquires the IP address corresponding to the FQDN.

Furthermore, in the embodiment, a teleconference system is used as anexample of the communication system 1, but the present invention is notlimited thereto, and may be a telephone system such as an IP phone or anInternet phone. Furthermore, the communication system 1 may be anautomotive navigation system. In such a case, for example, one terminal10 corresponds to an automotive navigation device deployed on a vehicle,and the other terminal 10 corresponds to a management terminal or amanagement server in a management center where the automotive navigationsystem is managed, or corresponds to an automotive navigation devicedeployed on another vehicle. Furthermore, the communication system 1 maybe a communication system of mobile phones. In such a case, the terminal10 corresponds to a mobile phone, for example.

Furthermore, in the embodiment, image data and audio data are explainedas examples of communication data, but the present invention is notlimited thereto, and the communication data may be tactile data. In sucha case, the feeling of a user touching one terminal is communicated tothe other terminal. Furthermore, the communication data may be smelldata. In such a case, the smell on one terminal is communicated to theother terminal. Furthermore, the communication data may be at least oneof image data, audio data, tactile data, and smell data.

Furthermore, explained in the embodiment is an example in which ateleconference is held over the communication system 1, but the presentinvention is not limited thereto, and the communication system 1 may beused in a meeting, a general conversation among a family or betweenfriends, or unidirectional presentation of information.

Furthermore, the external view of the communication terminal of theterminal illustrated in FIG. 6 is merely an example, and may be asmartphone, a tablet terminal, a mobile phone, or a general-purposepersonal computer (PC). A microphone or a camera does not necessarilyhave to be provided internally, and may be provided externally.

Furthermore, the signaling protocol on the request source terminal isexplained to be an instant messenger protocol (or an instant messengerprotocol extension) in FIGS. 2 and 4, and the signaling protocol of thedestination terminal is explained to be the SIP or H.323 in FIG. 4, butthese protocols are merely examples, and may also be any signalingprotocol other than those mentioned above.

Although the invention has been described with respect to specificembodiments for a complete and clear disclosure, the appended claims arenot to be thus limited but are to be construed as embodying allmodifications and alternative constructions that may occur to oneskilled in the art that fairly fall within the basic teaching herein setforth.

The invention claimed is:
 1. A communication terminal, comprising:processing circuitry that causes a display to display, beforetransmitting video data to a destination of communication, a functionselecting screen that contains a first icon for receiving a selection ofa first communication function and a second icon for receiving aselection of a second communication function, the first communicationfunction requiring communication using a first video codec for codingvideo, the second communication function requiring communication using asecond video codec for coding the video, the second video codec beingdifferent from that of the first communication function, executes thefirst communication function when the processing circuitry receives aselection of the first icon, and executes the second communicationfunction when the processing circuitry receives a selection of thesecond icon; and a transmitter that transmits the video data coded usingthe executed first communication function or the executed secondcommunication function to the destination, wherein the processingcircuitry causes the display to display a destination selecting screenfor receiving a selection of the destination of communication from amongdestination of communication candidates, receives, while the destinationselection screen is displayed, a selection of an image displayed on thedestination selection screen that causes display of the functionselecting screen, and causes the display to display the functionselecting screen directly in response to the received selection of theimage; and the transmitter transmits the video data coded using thefirst video codec when a communication initiating request is receivedfrom another communication terminal having only the first communicationfunction, while the function selecting screen containing the first andsecond icons is displayed, but before the processing circuitry receivesa selection of the first or second icons.
 2. The communication terminalaccording to claim 1, wherein the transmitter transmits operation statusinformation indicating that the second communication function is runningto a communication management system for managing an operation status ofthe communication terminal when the processing circuitry receives theselection of the second icon.
 3. The communication terminal according toclaim 1, wherein the processing circuitry causes the display to displayoperation statuses of the destination of communication candidates on thedestination selecting screen, and causes the display to display, inaddition to the destination selecting screen, a third icon as the imagethat causes display of the function selecting screen on the display;receives a selection of the third icon; and causes the display todisplay the function selecting screen when the selection of the thirdicon is received.
 4. The communication terminal according to claim 1,wherein the transmitter transmits the video data, which includes atleast audio data.
 5. The communication terminal according to claim 1,wherein the first video codec for the first communication function isH.264/Scalable Video Coding (SVC); and the second video codec for thesecond communication function is H.264/Advanced Video Coding (AVC). 6.The communication terminal according to claim 1, wherein the transmittertransmits the video data coded using the first video codec to thedestination of communication via a relay device when the firstcommunication function is executed, and directly transmits the videodata coded using the second video codec to the destination ofcommunication when the second communication function is executed.
 7. Thecommunication terminal according to claim 1, wherein the processingcircuitry establishes a session for transmitting the video data with thedestination of communication by using a signaling protocol when thefirst communication function or the second communication function isexecuted.
 8. The communication terminal according to claim 1, whereinthe first communication function is provided by a first communicationapplication installed in the communication terminal; and the secondcommunication function is provided by a second communication applicationdifferent from the first communication application, installed in thecommunication terminal.
 9. A method performed by a communicationterminal, comprising: causing, by processing circuitry, a display todisplay, before transmitting video data to a destination ofcommunication, a function selecting screen that contains a first iconfor receiving a selection of a first communication function and a secondicon for receiving a selection of a second communication function, thefirst communication function requiring communication using a first videocodec for coding video, the second communication function requiringcommunication using a second video codec for coding the video, thesecond video codec being different from that of the first communicationfunction; executing the first communication function when the processingcircuitry receives a selection of the first icon; executing the secondcommunication function when the processing circuitry receives aselection of the second icon; and transmitting the video data codedusing the executed first communication function or the executed secondcommunication function to the destination, wherein the method furtherincludes causing the display to display a destination selecting screenfor receiving a selection of the destination of communication from amongdestination of communication candidates, receiving, while thedestination selection screen is displayed, a selection of an imagedisplayed on the destination selection screen that causes display of thefunction selecting screen, and causing the display to display thefunction selecting screen directly in response to the received selectionof the image; and transmitting the video data coded using the firstvideo codec when a communication initiating request is received fromanother communication terminal having only the first communicationfunction, while the function selecting screen containing the first andsecond icons is displayed, but before the processing circuitry receivesa selection of the first or second icons.
 10. The method according toclaim 9, wherein the transmitting step comprises transmitting operationstatus information indicating that the second communication function isrunning to a communication management system for managing an operationstatus of the communication terminal when the processing circuitryreceives the selection of the second icon.
 11. The method according toclaim 9, further comprising: causing the display to display operationstatuses of the destination of communication candidates on thedestination selecting screen, and causing the display to display, inaddition to the destination selecting screen, a third icon as the imagethat causes display of the function selecting screen on the display;receiving a selection of the third icon; and causing the display todisplay the function selecting screen when the selection of the thirdicon is received.
 12. The method according to claim 9, wherein the videodata includes at least audio data.
 13. The method according to claim 9,wherein the first video codec for the first communication function isH.264/Scalable Video Coding (SVC); and the second video codec for thesecond communication function is H.264/Advanced Video Coding (AVC). 14.The method according to claim 9, wherein the transmitting step comprisestransmitting the video data coded using the first video codec to thedestination of communication via a relay device when the firstcommunication function is executed, and directly transmitting the videodata coded using the second video codec to the destination ofcommunication when the second communication function is executed. 15.The method according to claim 9, further comprising establishing asession for transmitting the video data with the destination ofcommunication by using a signaling protocol when the first communicationfunction or the second communication function is executed.
 16. Themethod according to claim 9, wherein the first communication function isprovided by a first communication application installed in thecommunication terminal; and the second communication function isprovided by a second communication application different from the firstcommunication application, installed in the communication terminal. 17.A non-transitory computer-readable medium storing a program which, whenexecuted by processing circuitry of a communication terminal, causes theprocessing circuitry to perform a method, comprising: causing a displayto display, before transmitting video data to a destination ofcommunication, a function selecting screen that contains a first iconfor receiving a selection of a first communication function and a secondicon for receiving a selection of a second communication function, thefirst communication function requiring communication using a first videocodec for coding video, the second communication function requiringcommunication using a second video codec for coding the video, thesecond video codec being different from that of the first communicationfunction; executing the first communication function when the processingcircuitry receives a selection of the first icon; executing the secondcommunication function when the processing circuitry receives aselection of the second icon; and transmitting the video data codedusing the executed first communication function or the executed secondcommunication function to the destination, wherein the method furtherincludes causing the display to display a destination selecting screenfor receiving a selection of the destination of communication from amongdestination of communication candidates, receiving, while thedestination selection screen is displayed, a selection of an imagedisplayed on the destination selection screen that causes display of thefunction selecting screen, and causing the display to display thefunction selecting screen directly in response to the received selectionof the image; and transmitting the video data coded using the firstvideo codec when a communication initiating request is received fromanother communication terminal having only the first communicationfunction, while the function selecting screen containing the first andsecond icons is displayed, but before the processing circuitry receivesa selection of the first or second icons.
 18. The computer-readablemedium according to claim 17, wherein the transmitting step comprisestransmitting operation status information indicating that the secondcommunication function is running to a communication management systemfor managing an operation status of the communication terminal when theprocessing circuitry receives the selection of the second icon.
 19. Thecomputer-readable medium according to claim 17, further comprising:causing the display to display operation statuses of the destination ofcommunication candidates on the destination selecting screen, andcausing the display to display, in addition to the destination selectingscreen, a third icon as the image that causes display of the functionselecting screen on the display; receiving a selection of the thirdicon; and causing the display to display the function selecting screenwhen the selection of the third icon is received.
 20. Thecomputer-readable medium according to claim 17, wherein the video dataincludes at least audio data.
 21. The computer-readable medium accordingto claim 17, wherein the first video codec for the first communicationfunction is H.264/Scalable Video Coding (SVC); and the second videocodec for the second communication function is H.264/Advanced VideoCoding (AVC).
 22. The computer-readable medium according to claim 17,wherein the transmitting step comprises transmitting the video datacoded using the first video codec to the destination of communicationvia a relay device when the first communication function is executed,and directly transmitting the video data coded using the second videocodec to the destination of communication when the second communicationfunction is executed.
 23. The computer-readable medium according toclaim 17, further comprising establishing a session for transmitting thevideo data with the destination of communication by using a signalingprotocol when the first communication function or the secondcommunication function is executed.
 24. The computer-readable mediumaccording to claim 17, wherein the first communication function isprovided by a first communication application installed in thecommunication terminal; and the second communication function isprovided by a second communication application different from the firstcommunication application, installed in the communication terminal.